Replace all use of inet_ntoa() with inet_ntop()

inet_ntoa() uses a statically-allocated buffer, which means that it wouldn't
be safe for use by an a multithreaded application using libopenconnect (as
yet hypothetical).

We should use inet_ntop() instead in all cases, even though it's slightly
less convenient.

Signed-off-by: Daniel Lenski <dlenski@gmail.com>

diff --git a/gpst.c b/gpst.c
index 86f357c65d17248d9498fd83a57040090b5b3420..1d59c2f6854b98c2a4ed3905123caa8ae085c0da 100644 (file)
--- a/gpst.c
+++ b/gpst.c
@@ -549,8 +549,9 @@ static int gpst_parse_config_xml(struct openconnect_info *vpninfo, xmlNode *xml_
                                inet_aton(new_ip_info.addr, &net_addr);
                                net_addr.s_addr &= nm_bits; /* clear host bits */
 
+                               char abuf[INET_ADDRSTRLEN];
                                if ((inc = malloc(sizeof(*inc))) == NULL ||
-                                   asprintf(&s, "%s/%s", inet_ntoa(net_addr), original_netmask) <= 0)
+                                   asprintf(&s, "%s/%s", inet_ntop(AF_INET, &net_addr, abuf, sizeof(abuf)), original_netmask) <= 0)
                                        return -ENOMEM;
                                inc->route = add_option_steal(&new_opts, "split-include", &s);
                                inc->next = new_ip_info.split_includes;

diff --git a/ppp.c b/ppp.c
index 37aab0473572bd3867544e4d7f6bc6b58c1e8c01..568fc0b522bd58ae5da0e7ad9974083b96399ebb 100644 (file)
--- a/ppp.c
+++ b/ppp.c
@@ -390,6 +390,7 @@ static int handle_config_request(struct openconnect_info *vpninfo,
        int ret;
        struct oc_ncp *ncp;
        unsigned char *p;
+       char abuf[MAX(INET_ADDRSTRLEN, INET6_ADDRSTRLEN)];
 
        switch (proto) {
        case PPP_LCP: ncp = &ppp->lcp; break;
@@ -462,10 +463,9 @@ static int handle_config_request(struct openconnect_info *vpninfo,
                        memcpy(&ppp->in_ipv4_addr, p+2, 4);
                        vpn_progress(vpninfo, PRG_DEBUG,
                                     _("Received peer IPv4 address %s from server\n"),
-                                    inet_ntoa(ppp->in_ipv4_addr));
+                                    inet_ntop(AF_INET, &ppp->in_ipv4_addr, abuf, sizeof(abuf)));
                        break;
                case PROTO_TAG_LEN(PPP_IP6CP, IP6CP_INT_ID, 8): {
-                       char buf[40];
                        unsigned char ipv6_ll[16] = {0xfe, 0x80, 0, 0, 0, 0, 0, 0};
 
                        /* XX: The server has allegedly sent us its link-local IPv6 address.
@@ -477,11 +477,9 @@ static int handle_config_request(struct openconnect_info *vpninfo,
                         */
                        memcpy(ipv6_ll + 8, p+2, 8);
                        memcpy(&ppp->in_ipv6_addr, ipv6_ll, 16);
-                       if (!inet_ntop(AF_INET6, &ppp->in_ipv6_addr, buf, sizeof(buf)))
-                               return -EINVAL;
                        vpn_progress(vpninfo, PRG_DEBUG,
                                     _("Received peer IPv6 link-local address %s from server\n"),
-                                    buf);
+                                    inet_ntop(AF_INET6, &ppp->in_ipv6_addr, abuf, sizeof(abuf)));
                        break;
                }
                default:
@@ -648,6 +646,7 @@ static int handle_config_rejnak(struct openconnect_info *vpninfo,
        struct oc_ppp *ppp = vpninfo->ppp;
        struct oc_ncp *ncp;
        unsigned char *p;
+       char abuf[MAX(INET_ADDRSTRLEN, INET6_ADDRSTRLEN)];
 
        switch (proto) {
        case PPP_LCP: ncp = &ppp->lcp; break;
@@ -698,10 +697,10 @@ static int handle_config_rejnak(struct openconnect_info *vpninfo,
                        break;
                case PROTO_TAG_LEN(PPP_IPCP, IPCP_IPADDR, 4): {
                        struct in_addr *a = (void *)(p + 2);
-                       const char *s = inet_ntoa(*a);
+                       inet_ntop(AF_INET, a, abuf, sizeof(abuf));
                        if (code == CONFNAK && a->s_addr) {
                                vpn_progress(vpninfo, PRG_DEBUG,
-                                            _("Server nak-offered IPv4 address: %s\n"), s);
+                                            _("Server nak-offered IPv4 address: %s\n"), abuf);
                                ppp->out_ipv4_addr = *a;
                                if (vpninfo->ip_info.addr) {
                                        vpn_progress(vpninfo, PRG_ERR,
@@ -711,7 +710,7 @@ static int handle_config_rejnak(struct openconnect_info *vpninfo,
                                }
                        } else {
                                vpn_progress(vpninfo, PRG_DEBUG,
-                                            _("Server rejected/nak'ed our IPv4 address or request: %s\n"), s);
+                                            _("Server rejected/nak'ed our IPv4 address or request: %s\n"), abuf);
                                return -EINVAL;
                        }
                        break;
@@ -721,14 +720,14 @@ static int handle_config_rejnak(struct openconnect_info *vpninfo,
                case PROTO_TAG_LEN(PPP_IPCP, IPCP_xNS_BASE + 2, 4):
                case PROTO_TAG_LEN(PPP_IPCP, IPCP_xNS_BASE + 3, 4): {
                        struct in_addr *a = (void *)(p + 2);
-                       const char *s = inet_ntoa(*a);
                        /* XX: see ppp.h for why bitfields work here */
                        int is_dns = t&1;
                        int entry = (t&2)>>1;
+                       inet_ntop(AF_INET, a, abuf, sizeof(abuf));
                        if (code == CONFNAK && a->s_addr) {
                                vpn_progress(vpninfo, PRG_DEBUG,
                                             _("Server nak-offered IPCP request for %s[%d] server: %s\n"),
-                                            is_dns ? "DNS" : "NBNS", entry, s);
+                                            is_dns ? "DNS" : "NBNS", entry, abuf);
                                ppp->nameservers[t & 3] = *a;
                                ppp->got_peerns |= (1<<(t-IPCP_xNS_BASE));
                        } else {
@@ -743,14 +742,12 @@ static int handle_config_rejnak(struct openconnect_info *vpninfo,
                case PROTO_TAG_LEN(PPP_IP6CP, IP6CP_INT_ID, 8): {
                        uint64_t *val = (void *)(p + 2);
                        if (code == CONFNAK && *val != 0) {
-                               char buf[40];
                                unsigned char ipv6_ll[16] = {0xfe, 0x80, 0, 0, 0, 0, 0, 0};
                                memcpy(ipv6_ll + 8, val, 8);
-                               if (!inet_ntop(AF_INET6, ipv6_ll, buf, sizeof(buf)))
-                                       return -EINVAL;
+                               inet_ntop(AF_INET6, ipv6_ll, abuf, sizeof(abuf));
 
                                vpn_progress(vpninfo, PRG_DEBUG,
-                                            _("Server nak-offered IPv6 link-local address %s\n"), buf);
+                                            _("Server nak-offered IPv6 link-local address %s\n"), abuf);
                                /* If we don't already have a valid global IPv6 address, then we are
                                 * supposed to use this one to create a valid link-local IPv6
                                 * address to allow autoconfiguration (https://tools.ietf.org/html/rfc5072)

diff --git a/script.c b/script.c
index 2ab66735351856997ccb2be4ca39638fd04a8ed5..d6f8bb8f0eccd259766097bde2d70b11d39f6262 100644 (file)
--- a/script.c
+++ b/script.c
@@ -118,7 +118,7 @@ static int process_split_xxclude(struct openconnect_info *vpninfo,
 {
        struct in_addr net_addr, mask_addr;
        const char *in_ex = include ? "IN" : "EX";
-       char envname[80], uptoslash[20];
+       char envname[80], uptoslash[20], abuf[INET_ADDRSTRLEN];
        const char *slash;
        char *endp;
        int masklen;
@@ -201,21 +201,22 @@ static int process_split_xxclude(struct openconnect_info *vpninfo,
        /* Fix incorrectly-set host bits */
        if (net_addr.s_addr & ~mask_addr.s_addr) {
                net_addr.s_addr &= mask_addr.s_addr;
+               inet_ntop(AF_INET, &net_addr, abuf, sizeof(abuf));
                if (include)
                        vpn_progress(vpninfo, PRG_ERR,
                                     _("WARNING: Split include \"%s\" has host bits set, replacing with \"%s/%d\".\n"),
-                                    route, inet_ntoa(net_addr), masklen);
+                                    route, abuf, masklen);
                else
                        vpn_progress(vpninfo, PRG_ERR,
                                     _("WARNING: Split exclude \"%s\" has host bits set, replacing with \"%s/%d\".\n"),
-                                    route, inet_ntoa(net_addr), masklen);
+                                    route, abuf, masklen);
        }
 
        snprintf(envname, 79, "CISCO_SPLIT_%sC_%d_ADDR", in_ex, *v4_incs);
-       script_setenv(vpninfo, envname, inet_ntoa(net_addr), 0, 0);
+       script_setenv(vpninfo, envname, inet_ntop(AF_INET, &net_addr, abuf, sizeof(abuf)), 0, 0);
 
        snprintf(envname, 79, "CISCO_SPLIT_%sC_%d_MASK", in_ex, *v4_incs);
-       script_setenv(vpninfo, envname, inet_ntoa(mask_addr), 0, 0);
+       script_setenv(vpninfo, envname, inet_ntop(AF_INET, &mask_addr, abuf, sizeof(abuf)), 0, 0);
 
        snprintf(envname, 79, "CISCO_SPLIT_%sC_%d_MASKLEN", in_ex, *v4_incs);
        script_setenv_int(vpninfo, envname, masklen);
@@ -322,13 +323,13 @@ void prepare_script_env(struct openconnect_info *vpninfo)
                                             _("Ignoring legacy network because netmask \"%s\" is invalid.\n"),
                                             vpninfo->ip_info.netmask);
                        else {
-                               char *netaddr;
+                               char netaddr[INET_ADDRSTRLEN];
                                int masklen = netmasklen(mask);
 
                                if (netmaskbits(masklen) != mask.s_addr)
                                        goto bad_netmask;
                                addr.s_addr &= mask.s_addr;
-                               netaddr = inet_ntoa(addr);
+                               inet_ntop(AF_INET, &addr, netaddr, sizeof(netaddr));
 
                                script_setenv(vpninfo, "INTERNAL_IP4_NETADDR", netaddr, 0, 0);
                                script_setenv(vpninfo, "INTERNAL_IP4_NETMASK", vpninfo->ip_info.netmask, 0, 0);