diff --git a/include/iscsi-private.h b/include/iscsi-private.h
index b91af60..b9f38f7 100644
--- a/include/iscsi-private.h
+++ b/include/iscsi-private.h
@@ -351,10 +351,11 @@ void* iscsi_zmalloc(struct iscsi_context *iscsi, size_t size);
 void* iscsi_realloc(struct iscsi_context *iscsi, void* ptr, size_t size);
 void iscsi_free(struct iscsi_context *iscsi, void* ptr);
 char* iscsi_strdup(struct iscsi_context *iscsi, const char* str);
+void* iscsi_smalloc(struct iscsi_context *iscsi, size_t size);
 void* iscsi_szmalloc(struct iscsi_context *iscsi, size_t size);
 void iscsi_sfree(struct iscsi_context *iscsi, void* ptr);
 
-unsigned long crc32c(char *buf, int len);
+uint32_t crc32c(uint8_t *buf, int len);
 
 struct scsi_task *iscsi_scsi_get_task_from_pdu(struct iscsi_pdu *pdu);
 
diff --git a/lib/crc32c.c b/lib/crc32c.c
index 0ae2cda..4455171 100644
--- a/lib/crc32c.c
+++ b/lib/crc32c.c
@@ -43,7 +43,7 @@
 /*                                                               */
 /*****************************************************************/
 
-static unsigned long crctable[256] = {
+uint32_t crctable[256] = {
  0x00000000L, 0xF26B8303L, 0xE13B70F7L, 0x1350F3F4L,
  0xC79A971FL, 0x35F1141CL, 0x26A1E7E8L, 0xD4CA64EBL,
  0x8AD958CFL, 0x78B2DBCCL, 0x6BE22838L, 0x9989AB3BL,
@@ -110,9 +110,9 @@ static unsigned long crctable[256] = {
  0xBE2DA0A5L, 0x4C4623A6L, 0x5F16D052L, 0xAD7D5351L
 };
 
-unsigned long crc32c(char *buf, int len)
+uint32_t crc32c(uint8_t *buf, int len)
 {
-	unsigned long crc = 0xffffffff;
+	uint32_t crc = 0xffffffff;
 	while (len-- > 0) {
 		crc = (crc>>8) ^ crctable[(crc ^ (*buf++)) & 0xFF];
 	}
diff --git a/lib/init.c b/lib/init.c
index 9941ceb..1b063cd 100644
--- a/lib/init.c
+++ b/lib/init.c
@@ -111,15 +111,22 @@ char* iscsi_strdup(struct iscsi_context *iscsi, const char* str) {
 	return str2;
 }
 
-void* iscsi_szmalloc(struct iscsi_context *iscsi, size_t size) {
+void* iscsi_smalloc(struct iscsi_context *iscsi, size_t size) {
 	void *ptr;
 	if (size > iscsi->smalloc_size) return NULL;
 	if (iscsi->smalloc_free > 0) {
 		ptr = iscsi->smalloc_ptrs[--iscsi->smalloc_free];
-		memset(ptr, 0, iscsi->smalloc_size);
 		iscsi->smallocs++;
 	} else {
-		ptr = iscsi_zmalloc(iscsi, iscsi->smalloc_size);
+		ptr = iscsi_malloc(iscsi, iscsi->smalloc_size);
+	}
+	return ptr;
+}
+
+void* iscsi_szmalloc(struct iscsi_context *iscsi, size_t size) {
+	void *ptr = iscsi_smalloc(iscsi, size);
+	if (ptr) {
+		memset(ptr, 0, size);
 	}
 	return ptr;
 }
diff --git a/lib/login.c b/lib/login.c
index dd0e7ab..36de085 100644
--- a/lib/login.c
+++ b/lib/login.c
@@ -1217,6 +1217,8 @@ iscsi_process_login_reply(struct iscsi_context *iscsi, struct iscsi_pdu *pdu,
 			must_have_chap_r = 0;
 		}
 
+		ISCSI_LOG(iscsi, 6, "TargetLoginReply: %s", ptr);
+
 		ptr  += len + 1;
 		size -= len + 1;
 	}
diff --git a/lib/pdu.c b/lib/pdu.c
index 1275b33..63adcc6 100644
--- a/lib/pdu.c
+++ b/lib/pdu.c
@@ -36,6 +36,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <inttypes.h>
 #include "iscsi.h"
 #include "iscsi-private.h"
 #include "scsi-lowlevel.h"
@@ -429,6 +430,20 @@ iscsi_process_pdu(struct iscsi_context *iscsi, struct iscsi_in_pdu *in)
 	uint8_t ahslen = in->hdr[4];
 	struct iscsi_pdu *pdu;
 
+	/* verify header checksum */
+	if (iscsi->header_digest != ISCSI_HEADER_DIGEST_NONE) {
+		uint32_t crc, crc_rcvd = 0;
+		crc = crc32c(in->hdr, ISCSI_RAW_HEADER_SIZE);
+		crc_rcvd |= in->hdr[ISCSI_RAW_HEADER_SIZE+0];
+		crc_rcvd |= in->hdr[ISCSI_RAW_HEADER_SIZE+1] << 8;
+		crc_rcvd |= in->hdr[ISCSI_RAW_HEADER_SIZE+2] << 16;
+		crc_rcvd |= in->hdr[ISCSI_RAW_HEADER_SIZE+3] << 24;
+		if (crc != crc_rcvd) {
+			iscsi_set_error(iscsi, "header checksum verification failed: calculated 0x%" PRIx32 " received 0x%" PRIx32, crc, crc_rcvd);
+			return -1;
+		}
+	}
+
 	if (ahslen != 0) {
 		iscsi_set_error(iscsi, "cant handle expanded headers yet");
 		return -1;
diff --git a/lib/socket.c b/lib/socket.c
index 036b4f4..8eee56d 100644
--- a/lib/socket.c
+++ b/lib/socket.c
@@ -366,6 +366,7 @@ iscsi_connect_async(struct iscsi_context *iscsi, const char *portal,
 	}
 
 	freeaddrinfo(ai);
+	strncpy(iscsi->connected_portal, portal, MAX_STRING_SIZE);
 	return 0;
 }
 
@@ -570,7 +571,7 @@ iscsi_read_from_socket(struct iscsi_context *iscsi)
 
 	if (iscsi->incoming == NULL) {
 		iscsi->incoming = iscsi_szmalloc(iscsi, sizeof(struct iscsi_in_pdu));
-		iscsi->incoming->hdr = iscsi_szmalloc(iscsi, ISCSI_RAW_HEADER_SIZE + ISCSI_DIGEST_SIZE);
+		iscsi->incoming->hdr = iscsi_smalloc(iscsi, ISCSI_HEADER_SIZE);
 		if (iscsi->incoming == NULL) {
 			iscsi_set_error(iscsi, "Out-of-memory: failed to malloc iscsi_in_pdu");
 			return -1;
@@ -675,6 +676,25 @@ iscsi_read_from_socket(struct iscsi_context *iscsi)
 	return 0;
 }
 
+static int iscsi_pdu_update_headerdigest(struct iscsi_context *iscsi, struct iscsi_pdu *pdu)
+{
+	uint32_t crc;
+
+	if (pdu->outdata.size < ISCSI_RAW_HEADER_SIZE + ISCSI_DIGEST_SIZE) {
+		iscsi_set_error(iscsi, "PDU too small (%u) to contain header digest",
+				(unsigned int) pdu->outdata.size);
+		return -1;
+	}
+
+	crc = crc32c(pdu->outdata.data, ISCSI_RAW_HEADER_SIZE);
+
+	pdu->outdata.data[ISCSI_RAW_HEADER_SIZE+3] = (crc >> 24);
+	pdu->outdata.data[ISCSI_RAW_HEADER_SIZE+2] = (crc >> 16);
+	pdu->outdata.data[ISCSI_RAW_HEADER_SIZE+1] = (crc >>  8);
+	pdu->outdata.data[ISCSI_RAW_HEADER_SIZE+0] = (crc);
+	return 0;
+}
+
 static int
 iscsi_write_to_socket(struct iscsi_context *iscsi)
 {
@@ -724,7 +744,13 @@ iscsi_write_to_socket(struct iscsi_context *iscsi)
 			
 			/* set exp statsn */
 			iscsi_pdu_set_expstatsn(iscsi->outqueue_current, iscsi->statsn + 1);
-			
+
+			/* calculate header checksum */
+			if (iscsi->header_digest != ISCSI_HEADER_DIGEST_NONE &&
+				iscsi_pdu_update_headerdigest(iscsi, iscsi->outqueue_current) != 0) {
+				return -1;
+			}
+
 			ISCSI_LIST_REMOVE(&iscsi->outqueue, iscsi->outqueue_current);
 			if (!(iscsi->outqueue_current->flags & ISCSI_PDU_DELETE_WHEN_SENT)) {
 				/* we have to add the pdu to the waitqueue already here
@@ -954,23 +980,6 @@ static int iscsi_tcp_queue_pdu(struct iscsi_context *iscsi,
 		return -1;
 	}
 
-	if (iscsi->header_digest != ISCSI_HEADER_DIGEST_NONE) {
-		unsigned long crc;
-
-		if (pdu->outdata.size < ISCSI_RAW_HEADER_SIZE + 4) {
-			iscsi_set_error(iscsi, "PDU too small (%u) to contain header digest",
-					(unsigned int) pdu->outdata.size);
-			return -1;
-		}
-
-		crc = crc32c((char *)pdu->outdata.data, ISCSI_RAW_HEADER_SIZE);
-
-		pdu->outdata.data[ISCSI_RAW_HEADER_SIZE+3] = (crc >> 24)&0xff;
-		pdu->outdata.data[ISCSI_RAW_HEADER_SIZE+2] = (crc >> 16)&0xff;
-		pdu->outdata.data[ISCSI_RAW_HEADER_SIZE+1] = (crc >>  8)&0xff;
-		pdu->outdata.data[ISCSI_RAW_HEADER_SIZE+0] = (crc)      &0xff;
-	}
-
 	iscsi_add_to_outqueue(iscsi, pdu);
 
 	return 0;
@@ -979,7 +988,7 @@ static int iscsi_tcp_queue_pdu(struct iscsi_context *iscsi,
 void
 iscsi_free_iscsi_in_pdu(struct iscsi_context *iscsi, struct iscsi_in_pdu *in)
 {
-	iscsi_free(iscsi, in->hdr);
+	iscsi_sfree(iscsi, in->hdr);
 	iscsi_free(iscsi, in->data);
 	in->data=NULL;
 	iscsi_sfree(iscsi, in);