Add some examples.

doc/crypto/EVP_PKEY_decrypt.pod

@@ -45,7 +45,37 @@ indicates the operation is not supported by the public key algorithm.
 
 Decrypt data using OAEP (for RSA keys):
 
-[to be added]
+ #include <openssl/evp.h>
+ #include <openssl/rsa.h>
+
+ EVP_PKEY_CTX *ctx;
+ unsigned char *out, *in;
+ size_t outlen, inlen; 
+ EVP_PKEY *key;
+ /* NB: assumes key in, inlen are already set up
+  * and that key is an RSA private key
+  */
+ ctx = EVP_PKEY_CTX_new(key);
+ if (!ctx)
+	/* Error occurred */
+ if (EVP_PKEY_decrypt_init(ctx) <= 0)
+	/* Error */
+ if (EVP_PKEY_CTX_set_rsa_padding(ctx, RSA_OAEP_PADDING) <= 0)
+	/* Error */
+
+ /* Determine buffer length */
+ if (EVP_PKEY_decrypt(ctx, NULL, &outlen, in, inlen) <= 0)
+	/* Error */
+
+ out = OPENSSL_malloc(outlen);
+
+ if (!out)
+	/* malloc failure */
+ 
+ if (EVP_PKEY_decrypt(ctx, out, &outlen, in, inlen) <= 0)
+	/* Error */
+
+ /* Decrypted data is outlen bytes written to buffer out */
 
 =head1 SEE ALSO
 

doc/crypto/EVP_PKEY_encrypt.pod

@@ -45,7 +45,37 @@ indicates the operation is not supported by the public key algorithm.
 
 Encrypt data using OAEP (for RSA keys):
 
-[to be added]
+ #include <openssl/evp.h>
+ #include <openssl/rsa.h>
+
+ EVP_PKEY_CTX *ctx;
+ unsigned char *out, *in;
+ size_t outlen, inlen; 
+ EVP_PKEY *key;
+ /* NB: assumes key in, inlen are already set up
+  * and that key is an RSA public key
+  */
+ ctx = EVP_PKEY_CTX_new(key);
+ if (!ctx)
+	/* Error occurred */
+ if (EVP_PKEY_encrypt_init(ctx) <= 0)
+	/* Error */
+ if (EVP_PKEY_CTX_set_rsa_padding(ctx, RSA_OAEP_PADDING) <= 0)
+	/* Error */
+
+ /* Determine buffer length */
+ if (EVP_PKEY_encrypt(ctx, NULL, &outlen, in, inlen) <= 0)
+	/* Error */
+
+ out = OPENSSL_malloc(outlen);
+
+ if (!out)
+	/* malloc failure */
+ 
+ if (EVP_PKEY_encrypt(ctx, out, &outlen, in, inlen) <= 0)
+	/* Error */
+
+ /* Encrypted data is outlen bytes written to buffer out */
 
 =head1 SEE ALSO
 

doc/crypto/EVP_PKEY_sign.pod

@@ -43,9 +43,42 @@ indicates the operation is not supported by the public key algorithm.
 
 =head1 EXAMPLE
 
-Sign data using PKCS#1 and SHA256 digest:
+Sign data using RSA with PKCS#1 padding and SHA256 digest:
+
+ #include <openssl/evp.h>
+ #include <openssl/rsa.h>
+
+ EVP_PKEY_CTX *ctx;
+ unsigned char *md, *sig;
+ size_t mdlen, siglen; 
+ EVP_PKEY *signing_key;
+ /* NB: assumes signing_key, md and mdlen are already set up
+  * and that signing_key is an RSA private key
+  */
+ ctx = EVP_PKEY_CTX_new(signing_key);
+ if (!ctx)
+	/* Error occurred */
+ if (EVP_PKEY_sign_init(ctx) <= 0)
+	/* Error */
+ if (EVP_PKEY_CTX_set_rsa_padding(ctx, RSA_PKCS1_PADDING) <= 0)
+	/* Error */
+ if (EVP_PKEY_CTX_set_signature_md(ctx, EVP_sha256()) <= 0)
+	/* Error */
+
+ /* Determine buffer length */
+ if (EVP_PKEY_sign(ctx, NULL, &siglen, md, mdlen) <= 0)
+	/* Error */
+
+ sig = OPENSSL_malloc(siglen);
+
+ if (!sig)
+	/* malloc failure */
+ 
+ if (EVP_PKEY_sign(ctx, sig, &siglen, md, mdlen) <= 0)
+	/* Error */
+
+ /* Signature is siglen bytes written to buffer sig */
 
-[to be added]
 
 =head1 SEE ALSO
 

doc/crypto/EVP_PKEY_verify.pod

@@ -48,7 +48,32 @@ the public key algorithm.
 
 Verify signature using PKCS#1 and SHA256 digest:
 
-[to be added]
+ #include <openssl/evp.h>
+ #include <openssl/rsa.h>
+
+ EVP_PKEY_CTX *ctx;
+ unsigned char *md, *sig;
+ size_t mdlen, siglen; 
+ EVP_PKEY *verify_key;
+ /* NB: assumes verify_key, sig, siglen md and mdlen are already set up
+  * and that verify_key is an RSA public key
+  */
+ ctx = EVP_PKEY_CTX_new(verify_key);
+ if (!ctx)
+	/* Error occurred */
+ if (EVP_PKEY_verify_init(ctx) <= 0)
+	/* Error */
+ if (EVP_PKEY_CTX_set_rsa_padding(ctx, RSA_PKCS1_PADDING) <= 0)
+	/* Error */
+ if (EVP_PKEY_CTX_set_signature_md(ctx, EVP_sha256()) <= 0)
+	/* Error */
+
+ /* Perform operation */
+ ret = EVP_PKEY_verify(ctx, md, mdlen, sig, siglen);
+
+ /* ret == 1 indicates success, 0 verify failure and < 0 for some
+  * other error.
+  */
 
 =head1 SEE ALSO
 

doc/crypto/EVP_PKEY_verifyrecover.pod

@@ -53,7 +53,39 @@ indicates the operation is not supported by the public key algorithm.
 
 Recover digest originally signed using PKCS#1 and SHA256 digest:
 
-[to be added]
+ #include <openssl/evp.h>
+ #include <openssl/rsa.h>
+
+ EVP_PKEY_CTX *ctx;
+ unsigned char *rout, *sig;
+ size_t routlen, siglen; 
+ EVP_PKEY *verify_key;
+ /* NB: assumes verify_key, sig and siglen are already set up
+  * and that verify_key is an RSA public key
+  */
+ ctx = EVP_PKEY_CTX_new(verify_key);
+ if (!ctx)
+	/* Error occurred */
+ if (EVP_PKEY_verifyrecover_init(ctx) <= 0)
+	/* Error */
+ if (EVP_PKEY_CTX_set_rsa_padding(ctx, RSA_PKCS1_PADDING) <= 0)
+	/* Error */
+ if (EVP_PKEY_CTX_set_signature_md(ctx, EVP_sha256()) <= 0)
+	/* Error */
+
+ /* Determine buffer length */
+ if (EVP_PKEY_verifyrecover(ctx, rout, &routlen, sig, siglen) <= 0)
+	/* Error */
+
+ rout = OPENSSL_malloc(routlen);
+
+ if (!rout)
+	/* malloc failure */
+ 
+ if (EVP_PKEY_verifyrecover(ctx, rout, &routlen, sig, siglen) <= 0)
+	/* Error */
+
+ /* Recovered data is routlen bytes written to buffer rout */
 
 =head1 SEE ALSO